Search results for: durability temperature soil mechanic
3829 Microstructure and Texture Evolution of Cryo Rolled and Annealed Ductile TaNbHfZrTi Refractory High Entropy Alloy
Authors: Mokali Veeresham
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The microstructure and texture evolution of cryo rolled and annealed ductile TaHfNbZrTi refractory high entropy alloy was investigated. To obtain that, the alloy is severely cryo rolled and subsequently annealed for the recrystallization process. The cryo rolled – 90% shows the presence of very fine grains and microstructural heterogeneity. The cryo rolled samples are annealed at a temperature ranging from 800°C to 1400°C, the partial recrystallization is observed at 800°C annealed condition, and at higher annealing temperatures the complete recrystallization process is noticed. The development of ND fiber texture is observed after the annealing.Keywords: refractory high entropy alloy, cryo-rolling, annealing, microstructure, texture
Procedia PDF Downloads 1793828 A Novel Eccentric Lapping Method with Two Rotatable Lapping Plates for Finishing Cemented Carbide Balls
Authors: C. C. Lv, Y. L. Sun, D. W. Zuo
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Cemented carbide balls are usually implemented in industry under the environment of high speed, high temperature, corrosiveness and strong collisions. However, its application is limited due to high fabrication cost, processing efficiency and quality. A novel eccentric lapping method with two rotatable lapping plates was proposed in this paper. A mathematical model was constructed to analyze the influence of each design parameter on this lapping method. To validate this new lapping method, an orthogonal experiment was conducted with cemented carbide balls (YG6). The simulation model was verified and the optimal lapping parameters were derived. The results show that the surface roundness of the balls reaches to 0.65um from 2um in 1 hour using this lapping method. So, using this novel lapping method, it can effectively improve the machining precision and efficiency of cemented carbide balls.Keywords: cemented carbide balls, eccentric lapping, high precision, lapping tracks, V-groove
Procedia PDF Downloads 3973827 Structural and Electromagnetic Properties of CoFe2O4-ZrO2 Nanocomosites
Authors: Ravinder Reddy Butreddy, Sadhana Katlakunta
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The nanocomposites of CoFe2O4-xZrO2 with different loadings of ZrO2 (x = 0.025, 0.05, 0.075, 0.1 and 1.5) were prepared using ball mill method. All the samples were prepared at 980°C/1h using microwave sintering method. The x-ray diffraction patterns show the existence of tetragonal/monoclinic phase of ZrO2 and cubic phase of CoFe2O4. The effects of ZrO2 on structural and microstructural properties of CoFe2O4 composite ceramics were investigated. It is observed that the density of the composite decreases and porosity increases with x. The magnetic properties such as saturation magnetization (Ms), and Coercive field were calculated at room temperature. The Ms is decreased with x while coercive field is increased with x. The dielectric parameters exhibit the relaxation behavior in high-frequency region and showing increasing trend with ZrO2 concentration, showing suitableKeywords: dielectric properties, magnetic properties, microwave sintering, nanocomposites
Procedia PDF Downloads 2413826 The Design, Development, and Optimization of a Capacitive Pressure Sensor Utilizing an Existing 9DOF Platform
Authors: Andrew Randles, Ilker Ocak, Cheam Daw Don, Navab Singh, Alex Gu
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Nine Degrees of Freedom (9 DOF) systems are already in development in many areas. In this paper, an integrated pressure sensor is proposed that will make use of an already existing monolithic 9 DOF inertial MEMS platform. Capacitive pressure sensors can suffer from limited sensitivity for a given size of membrane. This novel pressure sensor design increases the sensitivity by over 5 times compared to a traditional array of square diaphragms while still fitting within a 2 mm x 2 mm chip and maintaining a fixed static capacitance. The improved design uses one large diaphragm supported by pillars with fixed electrodes placed above the areas of maximum deflection. The design optimization increases the sensitivity from 0.22 fF/kPa to 1.16 fF/kPa. Temperature sensitivity was also examined through simulation.Keywords: capacitive pressure sensor, 9 DOF, 10 DOF, sensor, capacitive, inertial measurement unit, IMU, inertial navigation system, INS
Procedia PDF Downloads 5493825 Superlyophobic Surfaces for Increased Heat Transfer during Condensation of CO₂
Authors: Ingrid Snustad, Asmund Ervik, Anders Austegard, Amy Brunsvold, Jianying He, Zhiliang Zhang
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CO₂ capture, transport and storage (CCS) is essential to mitigate global anthropogenic CO₂ emissions. To make CCS a widely implemented technology in, e.g. the power sector, the reduction of costs is crucial. For a large cost reduction, every part of the CCS chain must contribute. By increasing the heat transfer efficiency during liquefaction of CO₂, which is a necessary step, e.g. ship transportation, the costs associated with the process are reduced. Heat transfer rates during dropwise condensation are up to one order of magnitude higher than during filmwise condensation. Dropwise condensation usually occurs on a non-wetting surface (Superlyophobic surface). The vapour condenses in discrete droplets, and the non-wetting nature of the surface reduces the adhesion forces and results in shedding of condensed droplets. This, again, results in fresh nucleation sites for further droplet condensation, effectively increasing the liquefaction efficiency. In addition, the droplets in themselves have a smaller heat transfer resistance than a liquid film, resulting in increased heat transfer rates from vapour to solid. Surface tension is a crucial parameter for dropwise condensation, due to its impact on the solid-liquid contact angle. A low surface tension usually results in a low contact angle, and again to spreading of the condensed liquid on the surface. CO₂ has very low surface tension compared to water. However, at relevant temperatures and pressures for CO₂ condensation, the surface tension is comparable to organic compounds such as pentane, a dropwise condensation of CO₂ is a completely new field of research. Therefore, knowledge of several important parameters such as contact angle and drop size distribution must be gained in order to understand the nature of the condensation. A new setup has been built to measure these relevant parameters. The main parts of the experimental setup is a pressure chamber in which the condensation occurs, and a high- speed camera. The process of CO₂ condensation is visually monitored, and one can determine the contact angle, contact angle hysteresis and hence, the surface adhesion of the liquid. CO₂ condensation on different surfaces can be analysed, e.g. copper, aluminium and stainless steel. The experimental setup is built for accurate measurements of the temperature difference between the surface and the condensing vapour and accurate pressure measurements in the vapour. The temperature will be measured directly underneath the condensing surface. The next step of the project will be to fabricate nanostructured surfaces for inducing superlyophobicity. Roughness is a key feature to achieve contact angles above 150° (limit for superlyophobicity) and controlled, and periodical roughness on the nanoscale is beneficial. Surfaces that are non- wetting towards organic non-polar liquids are candidates surface structures for dropwise condensation of CO₂.Keywords: CCS, dropwise condensation, low surface tension liquid, superlyophobic surfaces
Procedia PDF Downloads 2813824 Electrophysical and Thermoelectric Properties of Nano-scaled In2O3:Sn, Zn, Ga-Based Thin Films: Achievements and Limitations for Thermoelectric Applications
Authors: G. Korotcenkov, V. Brinzari, B. K. Cho
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The thermoelectric properties of nano-scaled In2O3:Sn films deposited by spray pyrolysis are considered in the present report. It is shown that multicomponent In2O3:Sn-based films are promising material for the application in thermoelectric devices. It is established that the increase in the efficiency of thermoelectric conversion at CSn~5% occurred due to nano-scaled structure of the films studied and the effect of the grain boundary filtering of the low energy electrons. There are also analyzed the limitations that may appear during such material using in devices developed for the market of thermoelectric generators and refrigerators. Studies showed that the stability of nano-scaled film’s parameters is the main problem which can limit the application of these materials in high temperature thermoelectric converters.Keywords: energy conversion technologies, thermoelectricity, In2O3-based films, power factor, nanocomposites, stability
Procedia PDF Downloads 2363823 Fabrication of Highly Conductive Graphene/ITO Transparent Bi-Film through Chemical Vapor Deposition (CVD) and Organic Additives-Free Sol-Gel Techniques
Authors: Bastian Waduge Naveen Harindu Hemasiri, Jae-Kwan Kim, Ji-Myon Lee
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Indium tin oxide (ITO) remains the industrial standard transparent conducting oxides with better performances. Recently, graphene becomes as a strong material with unique properties to replace the ITO. However, graphene/ITO hybrid composite material is a newly born field in the electronic world. In this study, the graphene/ITO composite bi-film was synthesized by a two steps process. 10 wt.% tin-doped, ITO thin films were produced by an environmentally friendly aqueous sol-gel spin coating technique with economical salts of In(NO3)3.H2O and SnCl4 without using organic additives. The wettability and surface free energy (97.6986 mJ/m2) enhanced oxygen plasma treated glass substrates were used to form voids free continuous ITO film. The spin-coated samples were annealed at 600 0C for 1 hour under low vacuum conditions to obtained crystallized, ITO film. The crystal structure and crystalline phases of ITO thin films were analyzed by X-ray diffraction (XRD) technique. The Scherrer equation was used to determine the crystallite size. Detailed information about chemical composition and elemental composition of the ITO film were determined by X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) coupled with FE-SEM respectively. Graphene synthesis was done under chemical vapor deposition (CVD) method by using Cu foil at 1000 0C for 1 min. The quality of the synthesized graphene was characterized by Raman spectroscopy (532nm excitation laser beam) and data was collected at room temperature and normal atmosphere. The surface and cross-sectional observation were done by using FE-SEM. The optical transmission and sheet resistance were measured by UV-Vis spectroscopy and four point probe head at room temperature respectively. Electrical properties were also measured by using V-I characteristics. XRD patterns reveal that the films contain the In2O3 phase only and exhibit the polycrystalline nature of the cubic structure with the main peak of (222) plane. The peak positions of In3d5/2 (444.28 eV) and Sn3d5/2 (486.7 eV) in XPS results indicated that indium and tin are in the oxide form only. The UV-visible transmittance shows 91.35 % at 550 nm with 5.88 x 10-3 Ωcm specific resistance. The G and 2D band in Raman spectroscopy of graphene appear at 1582.52 cm-1 and 2690.54 cm-1 respectively when the synthesized CVD graphene on SiO2/Si. The determined intensity ratios of 2D to G (I2D/IG) and D to G (ID/IG) were 1.531 and 0.108 respectively. However, the above-mentioned G and 2D peaks appear at 1573.57 cm-1 and 2668.14 cm-1 respectively when the CVD graphene on the ITO coated glass, the positions of G and 2D peaks were red shifted by 8.948 cm-1 and 22.396 cm-1 respectively. This graphene/ITO bi-film shows modified electrical properties when compares with sol-gel derived ITO film. The reduction of sheet resistance in the bi-film was 12.03 % from the ITO film. Further, the fabricated graphene/ITO bi-film shows 88.66 % transmittance at 550 nm wavelength.Keywords: chemical vapor deposition, graphene, ITO, Raman Spectroscopy, sol-gel
Procedia PDF Downloads 2623822 Numerical Study on Enhancement of Heat Transfer by Turbulence
Authors: Muhammad Azmain Abdullah, Ar Rashedul, Mohammad Ali
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This paper scrutinizes the influences of turbulence on heat transport rate, Nusselt number. The subject matter of this investigation also deals with the improvement of heat transfer efficiency of the swirl flow obtained by rotating a twisted tape in a circular pipe. The conditions to be fulfilled to observe the impact of Reynolds number and rotational speed of twisted tape are: a uniform temperature on the outer surface of the pipe, the magnitude of velocity of water varying from 0.1 m/s to 0.7 m/s in order to alter Reynolds number and a rotational speed of 200 rpm to 600 rpm. The gyration of twisted tape increase by 17%. It is also observed that heat transfer is exactly proportional to inlet gauge pressure and reciprocally proportional to increase of twist ratio.Keywords: swirl flow, twisted tape, twist ratio, heat transfer
Procedia PDF Downloads 2653821 The Friction and Wear Behavior of 0.35 VfTiC-Ti3SiC2 Composite
Authors: M. Hadji, A. Haddad, Y. Hadji
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The effects of boronizing treatment on the friction coefficient and wear behavior of 0.35 Vf TiC- Ti3 SiC2 composite were investigated. In order to modify the surface properties of Ti3SiC2, boronizing treatment was carried out through powder pack cementation in the 1150-1350 °C temperature range. After boronizing treatment, one mixture layer, composed of TiB2 and SiC, forms on the surface of Ti3SiC2. The growth of the coating is processed by inward diffusion of Boron and obeys a linear rule. The Boronizing treatment increases the hardness of Ti3SiC2 from 6 GPa to 13 GPa. In the pin-on-disc test, i twas found that the material undergoes a steady-state coefficient of friction of around 0.8 and 0.45 in case of Ti3SiC2/Al2O3 tribocouple under 7 N load for the non treated and the boronized samples, respectively. The wear resistance of Ti3SiC2 under Al2O3 ball sliding has been significantly improved, which indicated that the boronizing treatment is a promising surface modification way of Ti3SiC2.Keywords: MAX phase, boronizing, hardness, wear
Procedia PDF Downloads 3533820 Effect of Compost Application on Uptake and Allocation of Heavy Metals and Plant Nutrients and Quality of Oriental Tobacco Krumovgrad 90
Authors: Violina R. Angelova, Venelina T. Popova, Radka V. Ivanova, Givko T. Ivanov, Krasimir I. Ivanov
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A comparative research on the impact of compost on uptake and allocation of nutrients and heavy metals and quality of Oriental tobacco Krumovgrad 90 has been carried out. The experiment was performed on an agricultural field contaminated by the lead zinc smelter near the town of Kardzali, Bulgaria, after closing the lead production. The compost treatments had significant effects on the uptake and allocation of plant nutrients and heavy metals. The incorporation of compost leads to decrease in the amount of heavy metals present in the tobacco leaves, with Cd, Pb and Zn having values of 36%, 12% and 6%, respectively. Application of the compost leads to increased content of potassium, calcium and magnesium in the leaves of tobacco, and therefore, may favorably affect the burning properties of tobacco. The incorporation of compost in the soil has a negative impact on the quality and typicality of the oriental tobacco variety of Krumovgrad 90. The incorporation of compost leads to an increase in the size of the tobacco plant leaves, the leaves become darker in colour, less fleshy and undergo a change in form, becoming (much) broader in the second, third and fourth stalk position. This is accompanied by a decrease in the quality of the tobacco. The incorporation of compost also results in an increase in the mineral substances (pure ash), total nicotine and nitrogen, and a reduction in the amount of reducing sugars, which causes the quality of the tobacco leaves to deteriorate (particularly in the third and fourth harvests).Keywords: chemical composition, compost, heavy metals, oriental tobacco, quality
Procedia PDF Downloads 2793819 Influence of Physico-Chemical Changes in the Environment on the Behavior of Tadpoles Rana Saharica: Case of Fungicide (Artea 330ec)
Authors: S. Zouainia, R. Djebar, H. Berrebah, A. Sayeb
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This work focused on the study of physiological and biochemical changes observed in tadpoles exposed to fungicide Rana saharica Artea 330ec recently introduced in Algeria. For this, we tested the effect of xenobiotics on growth and development of tadpoles; among the studied parameters: total protein, glutathione and respiratory activity. The study of physiological parameters showed that the tadpoles change perfectly in the absence of toxic and in favorable conditions (pH, temperature). Our results showed an increased rate of protein and GSH in the presence of the fungicide Artea 330ec. The latter causes uninhibited very highly significant respiratory activity of tadpoles treated. The presence of xenobiotics in the breeding tadpoles water causes disturbances in behavior and food metabolism.Keywords: amphibians, fungicides, pesticides, pollution
Procedia PDF Downloads 4123818 Effect of Varied Climate, Landuse and Human Activities on the Termite (Isoptera: Insecta) Diversity in Three Different Habitats of Shivamogga District, Karnataka, India
Authors: C. M. Kalleshwaraswamy, G. S. Sathisha, A. S. Vidyashree, H. B. Pavithra
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Isoptera are an interesting group of social insects with different castes and division of labour. They are primarily wood-feeders, but also feed on a variety of other organic substrates, such as living trees, leaf litter, soil, lichens and animal faeces. The number of species and their biomass are especially large in tropics. In natural ecosystems, they perform a beneficial role in nutrient cycles by accelerating decomposition. The magnitude and dimension of ecological role played by termites is a function of their diversity, population density, and biomass. Termite assemblage composition has a strong response to habitat disturbance and may be indicative of quantitative changes in the decomposition process. Many previous studies in Western Ghat region of India suggest increased anthropogenic activities that adversely affect the soil macrofauna and diversity. Shivamogga district provides a good opportunity to study the effect of topography, cropping pattern, human disturbance on the termite fauna, thereby acquiring accurate baseline information for conservation decision making. The district has 3 distinct agro-ecological areas such as maidan area, semi-malnad and Western Ghat region. Thus, the district provides a unique opportunity to study the effect of varied climate and anthropogenic disturbance on the termite diversity. The standard protocol of belt transects method developed by Eggleton et al. (1997) was used for sampling termites. Sampling was done at monthly interval from September-2014 to August-2015 in Western Ghats, semi-malnad and maidan habitats. The transect was 100m long and 2m wide and divided into 20 contiguous sections, each 5 x 2m in each habitat. Within each section, all the probable microhabitats of termites were searched, which include dead logs, fallen tree, branch, sticks, leaf litter, vegetation etc.,. All the castes collected were labelled, preserved in 80% alcohol, counted and identified to species level. The number of encounters of a species in the transect was used as an indicator of relative abundance of species. The species diversity, species richness, density were compared in three different habitats such as Western Ghats, semi-malnad and maidan region. The study indicated differences in the species composition in the three different habitats. A total of 15 species were recorded which belonging to four sub family and five genera in three habitats. Eleven species viz., Odontotermes obesus, O. feae, O. anamallensis, O. bellahunisensis, O. adampurensis, O. boveni, Microcerotermes fletcheri, M. pakistanicus, Nasutitermes anamalaiensis, N. indicola, N. krishna were recorded in Western Ghat region. Similarly, 11 species viz., Odontotermes obesus, O. feae, O. anamallensis, O. bellahunisensis, O. hornii, O. bhagwathi, Microtermes obesi, Microcerotermes fletcheri, M. pakistanicus, Nasutitermes indicola and Pericapritermes sp. were recorded in semi-malnad habitat. However, only four species viz., O. obesus, O. feae, Microtemes obesi and Pericapritermes sp. species were recorded in maidan area. Shannon’s wiener diversity index (H) showed that Western Ghats had more species dominance (1.56) followed by semi- malnad (1.36) and lowest in maidan (0.89) habitats. Highest value of simpson’s index (D) was observed in Western Ghats habitat (0.70) with more diverse species followed by semi-malnad (0.58) and lowest in maidan (0.53). Similarly, evenness was highest (0.65) in Western Ghats followed by maidan (0.64) and least in semi-malnad habitat (0.54). Menhinick’s index (Dmn) value was ranging from 0.03 to 0.06 in different habitats in the study area. Highest index was observed in Western Ghats (0.06) followed by semi-malnad (0.05) and lowest in maidan (0.03). The study conclusively demonstrated that Western Ghat had highest species diversity compared to semi-malnad and maidan habitat indicating these two habitats are continuously subjected to anthropogenic disturbances. Efforts are needed to conserve the uncommon species which otherwise may become extinct due to human activities.Keywords: anthropogenic disturbance, isoptera, termite species diversity, Western ghats
Procedia PDF Downloads 2723817 Statistical and Analytical Comparison of GIS Overlay Modelings: An Appraisal on Groundwater Prospecting in Precambrian Metamorphics
Authors: Tapas Acharya, Monalisa Mitra
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Overlay modeling is the most widely used conventional analysis for spatial decision support system. Overlay modeling requires a set of themes with different weightage computed in varied manners, which gives a resultant input for further integrated analysis. In spite of the popularity and most widely used technique; it gives inconsistent and erroneous results for similar inputs while processed in various GIS overlay techniques. This study is an attempt to compare and analyse the differences in the outputs of different overlay methods using GIS platform with same set of themes of the Precambrian metamorphic to obtain groundwater prospecting in Precambrian metamorphic rocks. The objective of the study is to emphasize the most suitable overlay method for groundwater prospecting in older Precambrian metamorphics. Seven input thematic layers like slope, Digital Elevation Model (DEM), soil thickness, lineament intersection density, average groundwater table fluctuation, stream density and lithology have been used in the spatial overlay models of fuzzy overlay, weighted overlay and weighted sum overlay methods to yield the suitable groundwater prospective zones. Spatial concurrence analysis with high yielding wells of the study area and the statistical comparative studies among the outputs of various overlay models using RStudio reveal that the Weighted Overlay model is the most efficient GIS overlay model to delineate the groundwater prospecting zones in the Precambrian metamorphic rocks.Keywords: fuzzy overlay, GIS overlay model, groundwater prospecting, Precambrian metamorphics, weighted overlay, weighted sum overlay
Procedia PDF Downloads 1313816 Catalytic Deoxygenation of Propionic Acid in the Vapour Phase
Authors: Hossein Bayahia, Mohammed Saad Motlaq Al-Gahmdi
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The gas-phase deoxygenation of propionic acid was investigated in the presence of Co-Mo catalysts in N2 or H2 flow at 200-400 °C. In the presence of N2 the main product was 3-pentanone with other deoxygenates and some light gases: ethane and ethene. Using H2 flow, the catalyst was active for decarboxylation and decarbonylation of acid and the yields of ethane and ethene. The decarboxylation and decarbonylation reactions increased with increasing temperature. Cobalt-molybdenum supported on alumina showed better performance than bulk catalyst, especially at 400 °C in the presence of N2 for the ketonisation of propionic acid to form 3-pentanone as the main product. Bulk and supported catalysts were characterized by surface area porosity (BET), thermogravimetric analysis (TGA) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine adsorption.Keywords: deoxygenation, propionic acid, gas-phase, catalyst
Procedia PDF Downloads 2873815 Protection and Safeguarding of Groundwater in Algeria between Law and Right to Use
Authors: Aziez Ouahiba, Remini Boualem, Habi Mohamed
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The growth and the development of a pay are strongly related to the existence or the absence of water in this area, the sedentary lifestyle of the population makes that water demand is increasing and the different brandishing (dams, tablecloths or other) are increasingly solicited. In normal time rain and snow of the winter period reloads the slicks and the wadis that fill dams. Over these two decades, Global warming fact that temperature is increasingly high and rainfall is increasingly low, which induces a charge less and less important tablecloths, add to that the strong demand in irrigation. Our study will focus on the variation of rainfall and irrigation, Their effects on the degree of pollution of the groundwater in this area based on statistical analyses by the Xlstat (ACP, correlation...) software for a better explanation of these results and determine the hydrochemistry of different groups or polluted areas pou be able to offer adequate solutions for each area.Keywords: water in the basement, legislation, over exploitation, pollution, water prices
Procedia PDF Downloads 3843814 Optimization of Biodiesel Production from Sunflower Oil Using Central Composite Design
Authors: Pascal Mwenge, Jefrey Pilusa, Tumisang Seodigeng
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The current study investigated the effect of catalyst ratio and methanol to oil ratio on biodiesel production by using central composite design. Biodiesel was produced by transesterification using sodium hydroxide as a homogeneous catalyst, a laboratory scale reactor consisting of flat bottom flask mounts with a reflux condenser and a heating plate was used to produce biodiesel. Key parameters, including, time, temperature and mixing rate were kept constant at 60 minutes, 60 oC and 600 RPM, respectively. From the results obtained, it was observed that the biodiesel yield depends on catalyst ratio and methanol to oil ratio. The highest yield of 50.65% was obtained at catalyst ratio of 0.5 wt.% and methanol to oil mole ratio 10.5. The analysis of variances of biodiesel yield showed the R Squared value of 0.8387. A quadratic mathematical model was developed to predict the biodiesel yield in the specified parameters ranges.Keywords: ANOVA, biodiesel, catalyst, CCD, transesterification
Procedia PDF Downloads 2123813 Indoor Thermal Comfort in Educational Buildings in the State of Kuwait
Authors: Sana El-Azzeh, Farraj Al-Ajmi, Abdulrahman Al-Aqqad, Mohamed Salem
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Thermal comfort is defined according to ANSI/ASHRAE Standard 55 as a condition of mind that expresses satisfaction with the thermal environment and is assessed by subjective evaluation. Sustaining this standard of thermal comfort for occupants of buildings or other enclosures is one of the important goals of HVAC design engineers. This paper presents a study of thermal comfort and adaptive behaviors of occupants who occupies two locations at the campus of the Australian College of Kuwait. A longitudinal survey and field measurement were conducted to measure thermal comfort, adaptive behaviors, and indoor environment qualities. The study revealed that female occupants in the selected locations felt warmer than males and needed more air velocity and lower temperature.Keywords: indoor thermal comfort, educational facility, gender analysis, dry desert climate
Procedia PDF Downloads 1603812 Modeling Sorption and Permeation in the Separation of Benzene/ Cyclohexane Mixtures through Styrene-Butadiene Rubber Crosslinked Membranes
Authors: Hassiba Benguergoura, Kamal Chanane, Sâad Moulay
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Pervaporation (PV), a membrane-based separation technology, has gained much attention because of its energy saving capability and low-cost, especially for separation of azeotropic or close-boiling liquid mixtures. There are two crucial issues for industrial application of pervaporation process. The first is developing membrane material and tailoring membrane structure to obtain high pervaporation performances. The second is modeling pervaporation transport to better understand of the above-mentioned structure–pervaporation relationship. Many models were proposed to predict the mass transfer process, among them, solution-diffusion model is most widely used in describing pervaporation transport including preferential sorption, diffusion and evaporation steps. For modeling pervaporation transport, the permeation flux, which depends on the solubility and diffusivity of components in the membrane, should be obtained first. Traditionally, the solubility was calculated according to the Flory–Huggins theory. Separation of the benzene (Bz)/cyclohexane (Cx) mixture is industrially significant. Numerous papers have been focused on the Bz/Cx system to assess the PV properties of membrane materials. Membranes with both high permeability and selectivity are desirable for practical application. Several new polymers have been prepared to get both high permeability and selectivity. Styrene-butadiene rubbers (SBR), dense membranes cross-linked by chloromethylation were used in the separation of benzene/cyclohexane mixtures. The impact of chloromethylation reaction as a new method of cross-linking SBR on the pervaporation performance have been reported. In contrast to the vulcanization with sulfur, the cross-linking takes places on styrene units of polymeric chains via a methylene bridge. The partial pervaporative (PV) fluxes of benzene/cyclohexane mixtures in styrene-butadiene rubber (SBR) were predicted using Fick's first law. The predicted partial fluxes and the PV separation factor agreed well with the experimental data by integrating Fick's law over the benzene concentration. The effects of feed concentration and operating temperature on the predicted permeation flux by this proposed model are investigated. The predicted permeation fluxes are in good agreement with experimental data at lower benzene concentration in feed, but at higher benzene concentration, the model overestimated permeation flux. The predicted and experimental permeation fluxes all increase with operating temperature increasing. Solvent sorption levels for benzene/ cyclohexane mixtures in a SBR membrane were determined experimentally. The results showed that the solvent sorption levels were strongly affected by the feed composition. The Flory- Huggins equation generates higher R-square coefficient for the sorption selectivity.Keywords: benzene, cyclohexane, pervaporation, permeation, sorption modeling, SBR
Procedia PDF Downloads 3343811 Foodborne Disease Risk Factors Among Women in Riyadh, Saudi Arabia
Authors: Abdullah Alsayeqh
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The burden of foodborne diseases in Saudi Arabia is currently unknown. The objective of this study was to identify risk factors associated with these diseases among women in Riyadh. A cross-sectional study was carried out from March to July, 2013 where participants’ responses indicated that they were at risk of these diseases through improper food-holding temperature (45.28%), inadequate cooking (35.47%), cross-contamination (32.23%), and food from unsafe sources (22.39%). The claimed food safety knowledge by 22.04% of participants was not evidenced by their reported behaviors (p > 0.05). This is the first study to identify the gap in food safety knowledge among women in Riyadh which needs to be addressed by the concerned authorities in the country by engaging women more effectively in food safety educational campaigns.Keywords: foodborne diseases, risk factors, knowledge, women, Saudi Arabia
Procedia PDF Downloads 5143810 In Situ Production of Nano-Cu on a Cotton Fabric Surface by Ink-Jet Printing
Authors: N. Zoghi, Laleh Maleknia , M. E. Olya
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The nano-Cu particles were produced on cotton fabric substrate by ink-jet printing technology with water-soluble ink, which was based on copper. The surface tension and viscosity of the prepared inks were evaluated. The ink-jet printing process was repeated 1, 3, and 5 times in order to evaluate variations in the optical properties by changing thickness of printed film. Following initial drying of the printed film, the samples were annealed at different temperatures (150 °C, 200 °C and 250 °C) to determine the optimum temperature for the parameters set out in this experiment. The prepared nano-Cu particles were characterized by XRD and UV spectroscopy. The appearance of printed image and the nano-Cu particles morphology were observed by SEM. The results demonstrated that the ink-jet printing technology can be used to produce nano-particles on the cotton fabrics surface.Keywords: ink-jet printing, nano-cu, fabric ink, in situ production, cotton fabric, water-soluble ink, morphology
Procedia PDF Downloads 4353809 Effect of Different Salt Concentrations and Temperatures on Seed Germination and Seedling Characters in Safflower (Carthamus tinctorius L.) Genotypes
Authors: Rahim Ada, Zamari Temory, Hasan Dalgic
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Germination and seedling responses of seven safflower seed genotypes (Dinçer, Remzibey, Black Sun2 cultivars and A19, F4, I1, J19 lines) to different salinity concentrations (0, 5, 10, and 20 g l-1) and temperatures (10 and 20 oC) evaluated in Completely Randomized Factorial Designs in Department of Field Crops of Selcuk University, Konya, Turkey. Seeds in the control (distilled water) had at 10 and 20 oC the highest germination percentage (93.88 and 94.32 %), shoot length (4.60 and 8.72 cm), root length (4.27 and 6.54 cm), shoot dry weight (22.37 mg and 25.99 mg), and root dry weight (2.22 and 2.47 mg). As the salt concentration increased, values of all characters were decreased. In this experiment, in 20 g l-1 salt concentration found germination percentage (21.28 and 26.66 %), shoot (1.32 and 1.35 cm) and root length (1.04 and 1.10 cm), shoot (8.05 mg and 7.49 mg) and root dry weight (0.83 and 0.98 mg) at 10, and 20 oC.Keywords: safflower, NaCl, temperature, shoot and root length, salt concentration
Procedia PDF Downloads 2893808 Effects of Alkalinity on the Treatment of Landfill Leachate through Algae Growth
Authors: Tahir Imran Qureshi
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This study was aimed at finding out effects of potential influence of alkalinity on the treatment of landfill leachate through the growth of algae at varying dilution rates and toxicity potential. pH control proved to be an effective factor influencing on algal growth. With the use of algae Scenedesmus sp. for the treatment of leachate, a sharp increase in the growth of algae was recorded until pH 9. However, at pH 9.3 and 25 °C temperature, the growing trend of algae population showed a weakening tendency with the increase of total alkalinity in the leachate solution. Highest growth of algae was recorded in the leachate samples with alkalinity ranged at 1500-2500 mg CaCO3/L under neutral condition at pH 7 after 48 hours of cultivation time. Under the similar conditions, total nitrogen and total phosphorous in the leachate also reduced to 80% and 85%, respectively, however, no significant removal of COD was observed during the course of experiment.Keywords: leachate treatment, microalgae, nutrient removal, ammonia toxicity
Procedia PDF Downloads 3373807 Experimental Investigations on Group Interaction Effects of Laterally Loaded Piles in Submerged Sand
Authors: Jasaswini Mishra, Ashim K. Dey
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This paper aims to investigate the group interaction effects of laterally loaded pile groups driven into a medium dense sand layer in submerged state. Static lateral load tests were carried out on pile groups consisting of varying number of piles and at different spacings. The test setup consists of a load cell (500 kg capacity) and an LVDT (50 mm) to measure the load and pile head deflection respectively. The piles were extensively instrumented with strain gauges so as to study the variation of soil resistance within the group. The bending moments at various depths were calculated from strain gauge data and these curves were fitted using a higher order polynomial in order to get 'p-y' curves. A comparative study between a single pile and a pile under a group has also been done for a better understanding of the group effect. It is observed that average load per pile is significantly reduced relative to single pile and it decreases with increase in the number of piles in a pile group. The loss of efficiency of the piles in the group, commonly referred to as "shadowing" effect, has been expressed by the use of a 'p-multiplier'. Leading rows carries greater amount of load when compared with the trailing rows. The variations of bending moment with depth for different rows of pile within a group and different spacing have been analyzed and compared with that of a single pile. p multipliers within different rows in a pile group were evaluated from the experimental study.Keywords: group action, laterally loaded piles, p-multiplier, strain gauge
Procedia PDF Downloads 2433806 An Experimental Study to Control Single Droplet by Actuating Waveform with Preliminary and Suppressing Vibration
Authors: Oke Oktavianty, Tadayuki Kyoutani, Shigeyuki Haruyama, Ken Kaminishi
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For advancing the experiment system standard of Inkjet printer that is being developed, the actual natural period, fire limitation number in droplet weight measurement and observation distance in droplet velocity measurement was investigated. In another side, the study to control the droplet volume in inkjet printer with negative actuating waveform method is still limited. Therefore, the effect of negative waveform with preliminary and suppressing vibration addition on the droplet formation process, droplet shape, volume and velocity were evaluated. The different voltage and print-head temperature were exerted to obtain the optimum preliminary and suppressing vibration. The mechanism of different phenomenon from each waveform was also discussed.
Keywords: inkjet printer, DoD, waveform, preliminary and suppressing vibration
Procedia PDF Downloads 2423805 Design and Analysis of Piping System with Supports Using CAESAR-II
Authors: M. Jamuna Rani, K. Ramanathan
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A steam power plant is housed with various types of equipments like boiler, turbine, heat exchanger etc. These equipments are mainly connected with piping systems. Such a piping layout design depends mainly on stress analysis and flexibility. It will vary with respect to pipe geometrical properties, pressure, temperature, and supports. The present paper is to analyze the presence and effect of hangers and expansion joints in the piping layout/routing using CAESAR-II software. Main aim of piping stress analysis is to provide adequate flexibility for absorbing thermal expansion, code compliance for stresses and displacement incurred in piping system. The design is said to be safe if all these are in allowable range as per code. In this study, a sample problem is considered for analysis as per power piping ASME B31.1 code and the results thus obtained are compared.Keywords: ASTM B31.1, hanger, expansion joint, CAESAR-II
Procedia PDF Downloads 3683804 Selecting High Forage-yielding Alfalfa Populations in a Mediterranean Drought-prone Environment by Using High-throughput Phenotyping
Authors: Hamza Armghan Noushahi, Luis Inostroza, Viviana Barahona, Soledad Espinoza, Carlos Ovalleb, Katherine Quitral, Gustavo A. Lobos, Fernando Guerra, Shawn Kefauver, Alejandro del Pozo
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Introduction: One of the primary environmental factors affecting forage crop yield globally is drought, particularly in Mediterranean climatic conditions, where drought typically persists for 5-6 months, usually between October and March in countries like Chile. Alfalfa, a perennial forage crop with deep roots, employs a diverse range of drought-tolerant strategies at the physiological, morphological, and molecular levels. In the current study, 250 alfalfa half-sib populations containing different genetic makeups were grown for three growing seasons (2021 to 2023) to identify drought-resistant populations with high forage yield in two water regimes (irrigated and rainfed) under the Mediterranean drought-prone region of Central Chile, Cauquenes. The objectives were to i) develop new field phenotyping methods using remote sensing technologies such as Red-Green-Blue (RGB) and thermal cameras to identify high-yielding and drought-tolerant alfalfa populations, and ii) select outstanding genetic material for plant breeding. Material And Methods: Field phenotyping involves using remote sensing technology, including RGB and thermal cameras mounted on unmanned aerial vehicles, and measuring the forage yield of 250 alfalfa half-sib populations grown under rainfed and irrigated water regimes in a Mediterranean drought-prone environment, during three growing seasons (2021-2023). Both trials were arranged in an α-lattice experimental design with two replications. Each replicate has 10 partial blocks including 25 half-sib populations. RGB-derived indices and canopy temperature difference (CTD), determined by subtracting the canopy temperature (Tc) from the ambient temperature (Ta), were related with forage yield. Results And Discussion: Results indicate that forage yield exhibited significant variability among the alfalfa populations, in both rainfed and irrigated conditions. During winter, it ranged from 1.4- to 6.1 Mg ha-1 in rainfed conditions and from 1.4 to 8.2 Mg ha-1 under the irrigated regime. Total forage yield ranged from 3.7 to 14.7 Mg ha-1 in rainfed conditions and from 6.3 to 25.1 Mg ha-1 in the irrigated regime. Among half-sib populations, the most productive populations were AlfaL4-5 (parent SARDI7), AlfaL57-7 (parent WL903), and AlfaL62-9 (parent Baldrich350), which produced the highest (>13 Mg ha-1 mean total FY and > 4.5 Mg ha-1 mean winter FY during 2021-2023) forage yield in both water regimes. RGB indices Hue, Saturation, b*, v*, GA, and GGA exhibited positive correlations, whereas Intensity, Lightness, a*, and u* showed negative correlations with forage yield in both water regimes. In 2021, RGB-derived indices showed a weak correlation (r < 0.5) with CTD. However, strong correlations were observed in November 2022 (r = -0.8 to +0.8) and 2023 (r = -0.7 to +0.7), specifically in the irrigated regime, indicating better performance under higher water availability. Moreover, the CTD was negatively correlated with FY (r = -0.28 for rainfed and -0.32 for irrigated in 2021, r = -0.57 for rainfed and r = -0.76 for irrigated in 2022, and r = -0.34 for rainfed and r = -0.52 for irrigated in 2023) of 250 alfalfa half-sib populations. It is concluded that CTD and RGB-derived indices were the most effective tools for identifying drought-resistant populations grown in Mediterranean drought-prone environments. In rainfed alfalfa, the most highly productive populations were AlfaL29-4 (parent AS3), AlfaL61-9 (parent Genesis), and AlfaL4-7 (parent SARDI7). Meanwhile, in irrigated conditions, the alfalfa half-sib populations AlfaL56-4 (parent Venus) and AlfaL57-2 (parent WL903) demonstrated maximum FY. Conclusion: Alfalfa winter and total FY varied widely between the three growing seasons (2021-2023) under two water regimes, rainfed and irrigated. There were three alfalfa half-sib populations, AlfaL4-5 (parent SARDI7), AlfaL57-7 (parent WL903) and AlfaL62-9 (parent Baldrich350), that exhibited high FY in both water regimes, rainfed and irrigated. The thermal camera derived index CTD (Tc-Ta) showed negative correlation with FY and appeared to be the most powerful tool in identification of alfalfa genotypes grown under Chilean Mediterranean drought prone environment.Keywords: alfalfa, remote sensing, phenotyping, forage crop
Procedia PDF Downloads 153803 Bacteria Removal from Wastewater by Electrocoagulation Process
Authors: Boudjema Nouara, Mameri Nabil
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Bacteria have played an important role in water contamination as a consequence of organic pollution. In this study, an electrocoagulation process was adopted to remove fecal contamination and pathogenic bacteria from waste water. The effect of anode/cathodes materials as well as operating conditions for bacteria removal from water, such as current intensity and initial pH and temperature. The results indicated that the complete removal was achevied when using aluminium anode as anode at current intensity of 3A, initial pH of 7-8 and electrolysis time of 30 minutes. This process showed a bactericidal effect of 95 to 99% for the total and fecal coliforms and 99% to 100% for Eschercichia coli and fecal Streptococci. A decrease of 72% was recorded for sulphite-reducing Clostridia. Thus, this process has the potential to be one the options for treatment where high amount of bacteria in wastewater river.Keywords: bacteria, el Harrach river, electrocoagulation, wastewater, treatment
Procedia PDF Downloads 4993802 Reconstructability Analysis for Landslide Prediction
Authors: David Percy
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Landslides are a geologic phenomenon that affects a large number of inhabited places and are constantly being monitored and studied for the prediction of future occurrences. Reconstructability analysis (RA) is a methodology for extracting informative models from large volumes of data that work exclusively with discrete data. While RA has been used in medical applications and social science extensively, we are introducing it to the spatial sciences through applications like landslide prediction. Since RA works exclusively with discrete data, such as soil classification or bedrock type, working with continuous data, such as porosity, requires that these data are binned for inclusion in the model. RA constructs models of the data which pick out the most informative elements, independent variables (IVs), from each layer that predict the dependent variable (DV), landslide occurrence. Each layer included in the model retains its classification data as a primary encoding of the data. Unlike other machine learning algorithms that force the data into one-hot encoding type of schemes, RA works directly with the data as it is encoded, with the exception of continuous data, which must be binned. The usual physical and derived layers are included in the model, and testing our results against other published methodologies, such as neural networks, yields accuracy that is similar but with the advantage of a completely transparent model. The results of an RA session with a data set are a report on every combination of variables and their probability of landslide events occurring. In this way, every combination of informative state combinations can be examined.Keywords: reconstructability analysis, machine learning, landslides, raster analysis
Procedia PDF Downloads 733801 Conical Spouted Bed Combustor for Combustion of Vine Shoots Wastes
Authors: M. J. San José, S. Alvarez, R. López
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In order to prove the applicability of a conical spouted bed combustor for the thermal exploitation of vineyard pruning wastes, the flow regimes of beds consisting of vine shoot beds and an inert bed were established under different operating conditions. The effect of inlet air temperature on the minimum spouted velocity was evaluated. Batch combustion of vine shoots in a conical spouted bed combustor was conducted at temperatures in the range 425-550 ºC with an inert bed. The experimental values of combustion efficiency of vine shoot calculated from the concentration the exhaust gases were assessed. The high experimental combustion efficiency obtained evidenced the proper suitability of the conical spouted bed combustor for the thermal combustion of vine shoots.Keywords: biomass wastes, thermal combustion, conical spouted beds, vineyard wastes
Procedia PDF Downloads 2023800 Use of Data of the Remote Sensing for Spatiotemporal Analysis Land Use Changes in the Eastern Aurès (Algeria)
Authors: A. Bouzekri, H. Benmassaud
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Aurès region is one of the arid and semi-arid areas that have suffered climate crises and overexploitation of natural resources they have led to significant land degradation. The use of remote sensing data allowed us to analyze the land and its spatiotemporal changes in the Aurès between 1987 and 2013, for this work, we adopted a method of analysis based on the exploitation of the images satellite Landsat TM 1987 and Landsat OLI 2013, from the supervised classification likelihood coupled with field surveys of the mission of May and September of 2013. Using ENVI EX software by the superposition of the ground cover maps from 1987 and 2013, one can extract a spatial map change of different land cover units. The results show that between 1987 and 2013 vegetation has suffered negative changes are the significant degradation of forests and steppe rangelands, and sandy soils and bare land recorded a considerable increase. The spatial change map land cover units between 1987 and 2013 allows us to understand the extensive or regressive orientation of vegetation and soil, this map shows that dense forests give his place to clear forests and steppe vegetation develops from a degraded forest vegetation and bare, sandy soils earn big steppe surfaces that explain its remarkable extension. The analysis of remote sensing data highlights the profound changes in our environment over time and quantitative monitoring of the risk of desertification.Keywords: remote sensing, spatiotemporal, land use, Aurès
Procedia PDF Downloads 339